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    Re: V corrections?
    From: Gary LaPook
    Date: 2017 Mar 28, 07:48 -0700

    For some reason I remembered the siderial day was 23 hours, 56 minutes and 3.9 seconds. I just Googled it and it says 23 hours, 56 minutes and 4.091 seconds. I can't believe that it has chnged almost 0.2 seconds in my lifetime but I remembered looking it up somewhere, about 50 years ago, and that is the value firmly planted in my head. I just looked at my 1937 American Ephemeris and Nautical Almanac at it has the "4.091" value so, wherever I got the "3.9" value, it was erroneous. 

    I remember in my meteorology class, the professor was lecturing about the geostrophic wind equation and he said that "the earth turns 360 degrees a day" and I corrected him, that it turns 361 degrees in a day( in inertial space, relevant to the wind formula) and I got an eraser thrown at me.

    gl

    ----------------------------------------------------------------

    Whoops!  Well spotted Noell.  Whilst proof reading I’m afraid I was so busy checking the grammar and still wondering why Aries was 15° 2.5’ per hour (presumably due to the sidereal day being four minutes shorter than the Solar day), that I missed the obvious. D

       
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